/* 
 * @(#)Throw.java	1.3 99/09/21
 * 
 * Copyright 1997, 1998, 1999 Sun Microsystems, Inc. All Rights
 * Reserved.
 * 
 * Sun grants you ("Licensee") a non-exclusive, royalty free,
 * license to use, modify and redistribute this software in source and
 * binary code form, provided that i) this copyright notice and license
 * appear on all copies of the software; and ii) Licensee does not 
 * utilize the software in a manner which is disparaging to Sun.
 *
 * This software is provided "AS IS," without a warranty of any
 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE 
 * HEREBY EXCLUDED.  SUN AND ITS LICENSORS SHALL NOT BE LIABLE 
 * FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, 
 * MODIFYING OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN 
 * NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST 
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
 * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER 
 * CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT 
 * OF THE USE OF OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS 
 * BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * This software is not designed or intended for use in on-line
 * control of aircraft, air traffic, aircraft navigation or aircraft
 * communications; or in the design, construction, operation or
 * maintenance of any nuclear facility. Licensee represents and warrants
 * that it will not use or redistribute the Software for such purposes.  
 */

import java.util.Hashtable;
import java.io.*;

import javax.naming.*;
import javax.naming.directory.*;

/**
 * Demonstrates how to search the directory while manually
 * following referrals.
 *
 * usage: java Throw
 */
class Throw {
    public static void main(String[] args) throws IOException {

	// Set up environment for creating initial context
	Hashtable env = new Hashtable(11);
	env.put(Context.INITIAL_CONTEXT_FACTORY, 
	    "com.sun.jndi.ldap.LdapCtxFactory");
	env.put(Context.PROVIDER_URL, "ldap://localhost:489/o=JNDITutorial");

	// Set referral property to throw ReferralException
	env.put(Context.REFERRAL, "throw");

	try {
	    // Create initial context
	    DirContext ctx = new InitialDirContext(env);

	    // Set controls for performing subtree search
	    SearchControls ctls = new SearchControls();
	    ctls.setSearchScope(SearchControls.SUBTREE_SCOPE);

	    // Do this in a loop because we don't know how
	    // many referrals there will be
	    for (boolean moreReferrals = true; moreReferrals;) {
		try {
		    // Perform search
		    NamingEnumeration answer = ctx.search("", "(objectclass=*)", 
			ctls);

		    // Print the answer
		    while (answer.hasMore()) {
			System.out.println(">>>" + 
			    ((SearchResult)answer.next()).getName());
		    }

		    // search completes with no more referrals
		    moreReferrals = false;

		} catch (ReferralException e) {

		    if (! followReferral(e.getReferralInfo())) {
			moreReferrals = e.skipReferral();
		    }
		    
		    // point to the new context
		    if (moreReferrals) {
			ctx = (DirContext) e.getReferralContext();
		    }
		}
	    }

	    // Close the context when we're done
	    ctx.close();
	} catch (NamingException e) {
	    e.printStackTrace();
	}
    }

    /**
      * Displays referral information and asks user whether to follow.
      */
    private static boolean followReferral(Object referralInfo) throws IOException {
	byte[] reply = new byte[4];

	System.out.println("Received referral: " + referralInfo);
	System.out.print("Follow it? [y/n]");
	System.in.read(reply);

	return (reply[0] != 'n');
    }
}

